(RNS) — Last year, a minor controversy erupted at the Islamic Society of North America’s annual convention in Chicago. ISNA had allowed two activist groups, the Human Rights Campaign and Muslims for Progressive Values, to co-sponsor a booth.

But when convention organizers saw what kind of content was being distributed, they shut the booth down.

As it turned out, organizers deemed objectionable items like HRC’s “Coming Home to Islam and Self” booklet and a Muslims for Progressive Values brochure advocating LGBT-inclusive prayer spaces. The latter group’s #ImamsForShe campaign, advocating for equality for Muslim women, felt out of step with what was supposed to be “a religious, private, and family-oriented event.”

This seemingly isolated event is symptomatic of a larger anomaly: the “strange bedfellows” dynamic between American Muslims and the progressive political establishment.

The pairing of Muslims and progressives is everywhere in evidence in the current midterm congressional election cycle. In July, New York congressional candidate and progressive darling Alexandria Ocasio-Cortez appeared at a “My Muslim Vote” event with Rashida Tlaib, who is a near lock to replace Michigan Congressman John Conyers and become the first Muslim woman in Congress.

In western Massachusetts, the hijab-wearing Tahirah Amatul-Wadud is running against a moderate Democrat in the Sept. 4 party primary. She has been endorsed by the Progressive Democrats of America and Indivisible National.

How is it that Muslims, who tend to be more socially conservative, have such an easy political affiliation with the Democratic Party? What accounts for Muslims’ ability to accept serious differences in ways that other religious groups often cannot? And is there more tension to this partnership than we know about?

A 2015 Pew survey shows Muslims have a higher intensity of belief and higher frequency of prayer than most Americans. They also showed lower support for a range of progressive values such as women working outside the home, abortion and same-sex marriage. This led Peter Beinart of The Atlantic to conclude, “In their religious devotion and attitudes toward gender and sexuality, American Muslims resemble evangelical Christians and traditional Catholics far more than they resemble secular progressives.”

One possible explanation is that Muslims are able to abide a political coalition with divergent values in ways that conservative white Protestants and Catholics simply cannot. It’s not that Muslims don’t see the disconnect with some parts of the Democratic political platform; they may simply feel little imperative to use government to promote those values. As a minority, they might not expect to make their values normative for everyone.

Thus, it may be tenable for Muslims to embrace traditional attitudes in their own homes and families while still tolerating a permissive society with an expansive view of individual rights and sexual liberation.

Frank Parmir, the Muslims for Progressive Values associate who was kicked out of the ISNA convention, explained it this way: “(T)hey are very uncomfortable with MPV’s advocacy of gender equality or LGBTQ inclusion.” But, he said, “They are glad to affirm HRC’s advocacy of legal rights for sexual minorities.”

This is a marked contrast from conservative Christians, who want law and policy to defend and promote their vision and get fussy when the Republican Party deviates from their social agenda at all.

Another explanation is more tribal. In the present political environment, Muslims seem to be offered two stark choices: one party that is ever more hostile to them, and one party that affectionately welcomes them.

Perhaps Muslims plant their flag in the Democratic Party coalition not because of shared beliefs about LGBT rights (or the ideal top marginal tax rate), but rather due to a shared embrace of a browner, more pluralistic society. You play for the team that wants you, not the team that hates you.

The current alignment has not always been the case — before 9/11 Muslims were about evenly split between the two parties. Since the cataclysm, growing GOP hostility to migrants and ever more blatant white-nativist appeals mean that Muslims have nowhere else to go in American politics.

But Democrats should not welcome Muslims into the party while requiring them to leave their beliefs about marriage and sexuality at the door.

Some argue that’s exactly what has happened. There is a real concern that accepting Muslims as a minority — for their brownness, as it were — deforms Islam into an ethnic identity that accords with a victim ideology acceptable to the social-justice left.

Debates will continue about how Muslims negotiate tensions between faith and politics. Perhaps one day the GOP will meaningfully compete for Muslim votes again. Or maybe Islam in America will take the path of liberal Protestantism, finding in the Democratic Party platform the ultimate political expression of its aims.

Until then, this fascinating puzzle challenges Americans of all faiths and none to reflect critically on what we value and how our deepest beliefs come to be promoted and defended in the public square.